Extract Even Bits Only from 32-bit Register

#include <stdio.h>
#include <stdint.h>

uint32_t extract_even_bits(uint32_t reg) {
    uint32_t a = 0, b, c;
    for(uint8_t i = 0; i < 32; i+=2){
        b = (reg >> i) & 0x01; 
        a|=(b << c);
        c++;
    }
    return a;
}

int main() {
    uint32_t reg;
    scanf("%u", &reg);
    printf("%u", extract_even_bits(reg));
    return 0;
}

Solving Approach